The invention relates to a method for improving the efficiency of the reoxygenation of water in line with a barrage, or dam, as well as a device designed for putting this method into practice.
It is known that dissolved oxygen forms an important factor in the quality of the water of a river, for it promotes aquatic life and the biodegradation of organic waste. Barrages, which create a certain difference in level, contribute to reoxygenating the flow in proportions which are all the higher the lower the oxygen content upstream. This reoxygenation is achieved by means of an overflow, formed by the water fall from the crown of the dam to the downstream water level. This overflow profits in fact from a certain oxygenation by diffusion, during the fall, through the air-water interface. In addition, it brings with it air bubbles which provide oxygenation of the water in depth.
The aim of the present invention is to improve the efficiency of reoxygenation of the water in line with a dam by an overflow and for this it proposes the use of a method which, while being simple to use and inexpensive, provides significant gains at the reoxygenation level.